Light emitting diode assembly and light emitting diode display device

ABSTRACT

An exemplary light emitting diode (LED) assembly includes a cover, a substrate, a LED unit, a first electrode terminal, and a second electrode terminal. The substrate includes a first surface and a second surface on an opposite side of the substrate thereto. The substrate and the cover cooperatively define a cavity. The LED unit is received in the cavity. The first and the second electrode terminals extend from the second surface. The first electrode terminal is electrically connected to one of a positive lead and a negative lead of the LED unit and the second electrode terminal is electrically connected to the other. The second electrode terminal includes a first electrode portion and a second electrode portion symmetrically arranged at opposite sides of the first electrode terminal. The first and the second electrode portions are at least partially symmetrical with respect to the first electrode terminal.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is divisional application of application Ser.No. 12/017,310, filed on Jan. 21, 2008, entitled “LIGHT EMITTING DIODEASSEMBLY AND LIGHT EMITTING DIODE DISPLAY DEVICE”, assigned to the sameassignee, disclosure of which is incorporated herein by reference in itsentirety.

BACKGROUND

1. Technical Field

The present invention relates to light emitting diode assemblies andlight emitting diode display devices.

2. Discussion of Related Art

Light emitting diode (LED) assemblies having various sizes and displayeffects have been developed and are available in the market. Dependingon the complexity of the required illumination pattern, most LED displaydevices include a number of LED assemblies arranged in an array andselectively switchable on/off to generate such an illumination pattern.

Referring to FIG. 10, a typical LED display device is provided. The LEDdisplay device includes a number of lead-frame LED assemblies 91, apositioning member 92, and a printed circuit board 93. In FIG. 10, onlyone LED assembly 91 is shown for the purpose of illustration. The LEDassemblies 91 each have a positive electrode 911 and a negativeelectrode 912. The positioning member 92 defines a number of positioningholes 920 penetrating therethrough. The LED assemblies 91 each isinstalled in a corresponding positioning hole 920 and the positiveelectrode 911 and the negative electrode 912 are soldered on andpenetrate through the printed circuit board 93.

In assembly of the LED display device, because each of the LEDassemblies 91 is a unidirectional conduction device, the positive andthe negative electrodes 911, 912 of each of the LED assemblies 91 arenecessary to be distinguished beforehand, then the LED assemblies 91 arecorrectly electrically connected with the printed circuit board 93.However, distinguishing between the positive and the negative electrodes911, 912 is time consuming.

Therefore, what is needed is a LED assembly, and a LED display devicewith a simplified and effective assembling process.

SUMMARY

A preferred embodiment provides a light emitting diode (LED) assembly.The LED assembly includes a cover, a substrate, a LED unit, a firstelectrode terminal, and a second electrode terminal. The substrateincludes a first surface and a second surface on an opposite side of thesubstrate to the first surface. The substrate and the covercooperatively define a cavity. The LED unit is received in the cavity.The first electrode terminal and the second electrode terminal extendfrom the second surface of the substrate. The first electrode terminalis electrically connected to one of a positive lead and a negative leadof the light emitting diode unit. The second electrode terminal iselectrically connected to the other of the positive lead and thenegative lead thereof. The second electrode terminal includes a firstelectrode portion and a second electrode portion symmetrically arrangedat opposite sides of the first electrode terminal. The first electrodeportion and the second electrode portion are at least partiallysymmetrical with respect to the first electrode terminal.

Another preferred embodiment provides a LED display device. The LEDdisplay device includes a plurality of LED assemblies as describedabove, a positioning member, and a circuit board. The positioning memberis fixed on the circuit board and the positioning member defines aplurality of positioning holes configured for receiving the LEDassemblies. The circuit board includes a plurality of electrode padunits each comprising a first electrode pad and a second electrode padelectrically connected with the respective first electrode terminal andthe second electrode terminal.

Detailed features of the present LED assembly and LED display devicewill become more apparent from the following detailed description andclaims, and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present LED assembly and LED display device can bebetter understood with reference to the following drawings. Thecomponents in the drawings are not necessarily drawn to scale, theemphasis instead being placed upon clearly illustrating the principlesof the present LED assembly and LED display device. Moreover, in thedrawings, like reference numerals designate corresponding partsthroughout the several views, wherein:

FIG. 1 is a schematic, front view of a LED assembly, according to afirst exemplary embodiment;

FIG. 2 is a bottom view of the LED assembly shown in FIG. 1;

FIG. 3 is a schematic, isometric view of a LED display device, accordingto an exemplary embodiment, employing the LED assembly as shown in FIG.1;

FIG. 4 is a schematic, front view of a LED assembly, according to asecond exemplary embodiment;

FIG. 5 is a schematic, front view of a LED assembly with an alternativeconfiguration of magnetic members, according to the second exemplaryembodiment;

FIG. 6 is a schematic, bottom view of a LED assembly, according to athird exemplary embodiment;

FIG. 7 is a schematic, bottom view of a LED assembly, according to afourth exemplary embodiment;

FIG. 8 is a schematic, bottom view of a LED assembly, according to afifth exemplary embodiment;

FIG. 9 is a schematic, bottom view of a LED assembly, according to asixth exemplary embodiment;

FIG. 10 is a schematic, isometric view of a conventional LED displaydevice employing a number of LED assemblies.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made to the drawings to describe the preferredembodiments of the light emitting diode (LED) assembly and the LEDdisplay device, in detail.

Referring now particularly to FIGS. 1 and 2, a LED assembly 20,according to a first exemplary embodiment, is provided. The LED assembly20 includes a cover 21, a substrate 22, a LED unit 23, a first electrodeterminal 24 and a second electrode terminal 25.

The cover 21 is suitably made of light transmissive materials such asplastic, resin and glass.

The substrate 22 is a glass fiber board, a flexible printed circuitboard or a ceramic board. The substrate 22 includes a first surface 220and a second surface 222 on an opposite side of the substrate 22 to thefirst surface 220. The first surface 220 and the cover 21 cooperativelydefine a cavity 210.

The LED unit 23 may be a LED lamp such as a surface mount device LEDlamp, a chip on board LED lamp, and a lead frame LED lamp. In theillustrated embodiment, the LED unit 23 is a lead frame LED lampreceived in the cavity 210. The LED unit 23 includes an encapsulationbody 230, a first lead 232 and a second lead 234. Alternatively, the LEDunit 23 also may be a LED chip electrically connected with the firstelectrode terminal 24 and the second electrode terminal 25 by wirebonding.

Referring to FIG. 2, the first electrode terminal 24 and the secondelectrode terminal 25 extend from the second surface 222 of thesubstrate 22. The first electrode terminal 24 is electrically connectedto one of a positive lead and a negative lead of the LED unit 23, andthe second electrode terminal 25 is electrically connected to the otherof the positive lead and the negative lead thereof. The second electrodeterminal 25 includes a first electrode portion 250 and a secondelectrode portion 252 arranged at both sides of the first electrodeterminal 24. The first electrode portion 250 and the second electrodeportion 252 have an identical bar-shape. The first electrode portion 250and the second electrode portion 252 are suitably symmetrical withrespect to the first electrode terminal 24.

Referring to FIG. 3, a LED display device 30 employing a number of LEDassemblies 20 is provided. It is noted that only one LED assembly 20 isshown for the purpose for illustration. The LED display device 30further includes a positioning member 31 and a circuit board 32.

The positioning member 31 defines a number of positioning holes 310arranged in an array and the positioning holes 310 are configured (i.e.,structured and arranged) for receiving the LED assembly 20. Thepositioning member 31 is fixed on the circuit board 32. The positioningmember 31 is made from a material selected from a group consisting ofplastics and alloys.

The circuit board 32 includes a plurality of electrode pad units thateach comprise a first electrode pad 320 and a second electrode pad 322.The first electrode pad 320 and the second electrode pad 322 areelectrically connected to an interior circuitry of the circuit board 32.The first electrode pads 320 and the second electrode pads 322 arerespectively electrically connected to a corresponding one of the firstelectrode terminal 24 and the second electrode terminal 25. As such,when the LED assembly 22 is received in the positioning hole 310, thecircuit board 32 supplies electrical power to the first and secondelectrode terminals 24, 25 by the first and second electrode pads 320and 322.

Because the first electrode portion 250 and the second electrode portion252 of the second electrode terminal 25 are symmetrical with respect tothe first electrode terminal 24, even when the LED assembly 20 isrotated round OO′ by 180 degrees and assembled into the through hole310, the first and second electrode terminals 24 and 25 can still drawpower normally from the first and second electrode pads 320 and 322 withproper polarity.

Referring to FIG. 4, a LED assembly 40, according to a second exemplaryembodiment, is provided. The configuration of the LED assembly 40 isgenerally similar to the above-mentioned LED assembly 20. However, theLED assembly 40 further includes magnetic members 46 arranged on thefirst surface 420 of the substrate 42 and received in the cavity 410.The magnetic members 46 are made of a material selected from a groupconsisting of iron, aluminum-nickel-cobalt (Al—Ni—Co),neodymium-iron-boron (Nd—Fe—B) and samarium-cobalt (Sm—Co). When the LEDassembly 40 is employed in the LED display device 30, the firstelectrode pads 320 and the second electrode pads 322 of the LED displaydevice 30 can be magnetic electrodes. When the LED assembly 40 isassembled into the positioning hole 310 of the positioning member 31,the LED assembly 40 would be fixed in the positioning hole 310 by amagnetic force between the magnetic members 46 and the first and secondelectrode pads 320 and 322, thus making assembly of the LED displaydevice 30 simple and convenient.

Referring to FIG. 5, alternatively, the magnetic members 46 also can bedisposed on the second surface 422 of the substrate 42 and at theoutside of the cavity 410. At least one of the first electrode terminal44 and the second electrode terminal 45 is electrically insulated fromthe magnetic members 46.

It is noted that, the first electrode portion 250 and the secondelectrode portion 252 of the second electrode terminal 25 is not limitedto being bar-shaped. The first electrode portion 250 and the secondelectrode portion 252 of the second electrode terminal 25 also may haveother shapes, as long as the polarity of the LED assembly is stillcorrect after being rotated round its central axis (shown as OO′ in FIG.3) by a certain angle and assembled into the positioning hole 310.

Referring to FIG. 6, a LED assembly 50 according to a third exemplaryembodiment of the present invention is provided. The configuration ofthe LED assembly 50 is generally similar to the above-mentioned LEDassembly 10. However, the first electrode portion 550 and the secondelectrode portion 552 of the second electrode terminal each have asemi-circular ring shape held in contact with each other.

Referring to FIG. 7, a LED assembly 60 according to a fourth exemplaryembodiment of the present invention is provided. The configuration ofthe LED assembly 60 is generally similar to the above-mentioned LEDassembly 10. However, the first electrode portion 650 and the secondelectrode portion 652 of the second electrode terminal each has a brokensemi-circular ring shape which does not contact the other.

Referring to FIG. 8, a LED assembly 70 according to a fifth exemplaryembodiment of the present invention is provided. The configuration ofthe LED assembly 70 is generally similar to the above-mentioned LED 10.However, the first electrode portion 750 and the second electrodeportion 752 of the second electrode terminal each have semi-ellipticalring shapes, and contact with each other.

When the first electrode portion and the second electrode portion of thesecond electrode terminal have bar, semi-circular ring, brokensemi-circular ring or semi-elliptic ring shape, the second power supplyelectrode 322 of the light emitting diode display device 30 suitably hasa shape matching with the first electrode portion and the secondelectrode portion of the second electrode terminal. The first electrodeterminal may be round, ellipsoid, rectangular, triangular etc.Accordingly, the first power supply electrode 320 has a shape matchingwith the first electrode terminal.

Referring to FIG. 9, a LED assembly 80 according to a sixth exemplaryembodiment of the present invention is provided. The difference betweenthe LED assembly 80 and the above-mentioned LED assembly 10 is that, thefirst electrode portion 850 of the second electrode terminal 85 isbar-shaped, and the first electrode portion 850 includes two parts 850 aand 850 b. The second electrode portion 852 has identical size and shapeto the part 850 b. The second electrode portion 852 and the part 850 bare symmetrical with respect to the first electrode terminal 84. Whenemployed in the light emitting diode display device 30, even the lightemitting diode assembly 80 is rotated round its central axis by acertain angle and assembled into the through hole 310, the first andsecond electrode terminals 84 and 85 can also normally draw power fromthe first and second electrode pads 320 and 322 with proper polarity.

The above-mentioned LED assemblies 20, 40, 50, 60, 70, 80 each includesa first electrode terminal and a second electrode terminal. The secondelectrode terminal includes a first electrode portion and a secondelectrode portion. The first electrode portion and the second electrodeportion are at least partially symmetrical with respect to the firstelectrode terminal. When being assembled in to the light emitting diodedisplay device, the light emitting diode assembly always receivessatisfactory polarity power without requiring identification.

Finally, it is to be understood that the above-described embodiments areintended to illustrate rather than limit the invention. Variations maybe made to the embodiments without departing from the spirit of theinvention as claimed. The above-described embodiments illustrate thescope of the invention but do not restrict the scope of the invention.

1. A light emitting diode display device, comprising: a plurality oflight emitting assemblies each comprising: a cover; a substrateincluding a first surface and a second surface on an opposite side ofthe substrate to the first surface, the substrate and the covercooperatively defining a cavity; a light emitting diode unit received inthe cavity; a first electrode terminal and a second electrode terminalextending from the second surface of the substrate, the first electrodeterminal being electrically connected to one of a positive lead and anegative lead of the light emitting diode unit, the second electrodeterminal being electrically connected to the other of the positive leadand the negative lead thereof; the second electrode terminal including afirst electrode portion and a second electrode portion symmetricallyarranged at opposite sides of the first electrode terminal; and acircuit board with the light emitting assemblies mounted thereon, thecircuit board comprising a plurality of electrode pad units eachcomprising a first electrode pad and a second electrode pad electricallyconnected with the respective first electrode terminal and the secondelectrode terminal.
 2. The light emitting diode display device accordingto claim 1, further comprising a positioning member fixed on the circuitboard, the positioning member defining a plurality of positioning holesarranged in an array, the light emitting diode assemblies being receivedin the positioning holes.
 3. The light emitting diode display deviceaccording to claim 1, wherein the positioning member is made of amaterial selected from a group consisting of plastic and alloy.
 4. Thelight emitting diode display device according to claim 1, wherein thelight emitting assemblies each further comprise a magnetic member fixedon at least one of the first surface and the second surface of thesubstrate.
 5. The light emitting diode display device according to claim4, wherein the magnetic member is made of a material selected form agroup consisting of iron, aluminum-nickel-cobalt, neodymium-iron-boronand samarium-cobalt.
 6. The light emitting diode display deviceaccording to claim 1, wherein a section of the first electrode terminalhas a round, ellipsoid, rectangular or triangular shape.
 7. The lightemitting diode display device according to claim 1, wherein a section ofthe first electrode portion has a rectangular, semi-circular ring, orsemi-elliptical ring shape.
 8. The light emitting diode assemblyaccording to claim 1, wherein the first electrode portion and the secondelectrode portion contact with each other.
 9. A light emitting diodeassembly, comprising: a cover; a substrate including a first surface anda second surface on an opposite side of the substrate to the firstsurface, the first surface and the cover cooperatively defining acavity; a light emitting diode unit located in the cavity; a firstelectrode terminal and a second electrode terminal extending from thesecond surface of the substrate, the second electrode terminal beingarranged around the first electrode terminal, the first electrodeterminal and the second electrode terminal being electrically connectedwith positive and negative leads of the light emitting diode unit. 10.The light emitting diode assembly according to claim 9, wherein thesecond electrode terminal includes two parallel spaced bars, an circularring, a broken circular ring, an elliptical ring, or a broken ellipticalring.